I'm curious to know how the CT5 reacts to a 100k expression pedal. Using an 8-Step, which puts out voltage and not resistance, doesn't cause this behavior.
I sent a video to Scott as he suggested, but maybe someone else here can see if their CT5 acts like mine.
I've observed the same phenomenon described by Tall Walls where the FBK/RAND/DIR3 knob acts odd when the Expression Pedal input is used and selected for DIR1 (E switch in UP position). I use a custom-built 100Kohm expression pedal with the CT5 (Rev "K", FW 0.963) that has two 100Kohm pots and a momentary contact switch to select between them providing two adjustable "presets". It appears that in MODE1 under the described conditions, no matter where the 100k Expression Pedal pot is set the FBK/RAND/DIR3 knob is "added" to the Expression Pedal setting of DIR1. The FBK/RAND/DIR3 knob still controls Feedback but it also affects the DIR1 parameter. There is similar interaction in MODE2 and 3 but I'm still trying to characterize the behavior under those conditions. At this point I don't know whether to classify this as a bug or a feature ... It does seem as though it may be an unintended consequence of the pedal's design, at least when using a relatively high resistance expression pedal.